1983 FIAT UNO engine coolant

mounted on the front end of the crankshaft
and driven by it.
11The flexible toothed timing belt drives thecamshaft and the coolant pump from a
sprocket on the front end of the crankshaft.
The belt is tensioned by an
eccentrically-mounted pulley.
12The distributor and the fuel pump
(carburettor models) are driven from the
flywheel end of the camshaft. The fuel pump
on fuel injection models is an integral unit
combined with the fuel gauge sender unit and
immersed in the fuel tank.
PART B:
OPERATIONS POSSIBLE
WITH ENGINE IN CAR
Valve clearances - adjustment
1The operations are similar to those
described in Chapter 1, Section 26, but note
that the special tools referred to have differentpart numbers for the FlRE engine -
1860443000 and 1887001000 (photos).
2Remember that the clearance for inlet and
exhaust valves differs see Specifications at
the beginning of this Supplement.
3Counting from the timing cover end of the
engine, the valve sequence is as follows.
Inlet 2-4-5-7
Exhaust 1-3-6-8
Timing belt - renewal #
4Remove the air cleaner.
5Slacken and remove the alternator
drivebelt, then remove the spark plugs.
6Unbolt and remove the timing belt cover.
Note the bolt located at the bottom of the
cover, this can be easily overlooked (photo).
7Unbolt and remove the crankshaft pulley
(photo).
13•20 Supplement: Revisions and information on later models
5B.7 Unscrewing the crankshaft pulley
bolts5B.6 Timing cover lower fixing bolt
removal5B.1B Using a modified C-spanner and
screwdriver to remove a shim
5B.1A Checking a valve clearance
Fig. 13.3 Longitudinal sectional view of the 999 and 1108 cc
engine (Sec 5A)Fig. 13.4 999 and 1008 cc engine lubrication system (Sec 5A)

8Turn the crankshaft sprocket bolt, or
engage top gear and raise and turn a front
roadwheel, until the camshaft sprocket TDC
timing mark is aligned with the mark on the
cylinder head and the crankshaft sprocket
timing mark is aligned with the mark on the oil
pump cover (photos).
9Release the nut on the timing belt
tensioner, move the pulley away from the belt
and retighten the nut to hold the pulley in the
retracted position (photo).
10Slide the drivebelt from the sprockets.
11When refitting the new belt, make sure
that the sprocket timing marks are still in
alignment and fit the belt so that the arrows
on the belt point in the direction of engine
rotation, and the lines of the belt coincide with
the sprocket marks.
12Engage the timing belt with the crankshaft
sprocket first, then place it around the coolant
pump sprocket and the camshaft sprocket
(photo). Finally slip the belt around the
tensioner pulley.
13Release the tensioner nut and push the
pulley against the belt until the belt is quite
taut. Check that the sprocket timing marks
have not moved out of alignment. If they have,
reset them by moving them over the belt
teeth.
14Still applying force to the pulley, tighten its
nut.
15Turn the crankshaft through two complete
turns in the normal direction of rotation and
check that when the centre of the longest runof the belt is gripped between finger and
thumb it can just be twisted through 90º. If
increased tension is required to achieve this,
release the tensioner nut and prise the pulley
against the timing belt. Note: The above
procedure serves only as a rough guide to
setting the belt tension having it checked by a
FIAT dealer at the earliest opportunity is
recommended.
16Refit the timing belt cover, the crankshaft
pulley, alternator drivebelt, spark plugs and
the air cleaner.
Camshaft -
removal and refitting#
Warning: Refer to the beginning
of Section 9 before starting any
work.
17Remove the air cleaner and the fuel pump(carb. models), as described in Section 9 of
this Supplement.
18Remove the distributor (Section 10).
19Remove the timing belt cover.
20Unbolt and remove the camshaft cover,
having first disconnected the HT lead clip
(photos).
21Turn the crankshaft (by engaging top gear
and raising and turning a front roadwheel)
until No. 4 piston is at TDC. The timing mark
on the camshaft sprocket will be in alignment
with the mark on the cylinder head.
22Pass a rod through one of the holes in the
camshaft sprocket to prevent it rotating and
then unscrew the sprocket fixing bolt. Slip the
sprocket from the camshaft and out of the
loop of the belt (photos).
23Mark the camshaft bearing caps as to
position and then unbolt and remove the
Supplement: Revisions and information on later models 13•21
5B.9 Releasing the timing belt tensioner
nut5B.8B Crankshaft sprocket timing mark
and oil pump cover alignment mark
(arrowed)5B.8A Camshaft sprocket timing mark and
cylinder head timing mark in alignment
5B.22B Camshaft sprocket bolt and
washer5B.22A Unscrewing the camshaft sprocket
bolt
5B.20A Camshaft cover HT lead clip5B.12 Fitting the timing belt
5B.20B Removing the camshaft cover
13

depressurize the fuel system, before
disconnecting the fuel pipes and removing the
throttle body, as described in Section 9D.
34Disconnect the coolant and vacuum
hoses from the cylinder head and inlet
manifold (photo).
35Disconnect the electrical lead from the
coolant temperature switch, the LT leads from
the distributor and the idle cut-off solenoid
lead.
36Remove the distributor cap, disconnect
the plug leads and place the cap and leads to
one side of the engine compartment.
37Unbolt and remove the timing belt cover.
38Set No. 4 piston to TDC and then release
the timing belt tensioner and slip the belt from
the camshaft and coolant pump sprockets.
39Unbolt and remove the inlet manifold,
complete with carburettor, or throttle body as
applicable.
40Unbolt the exhaust manifold from the
cylinder head and tie it to one side of the
engine compartment; the downpipe bracket
will have to be disconnected.
41Unscrew the cylinder head bolts, a half
turn at a time in the reverse order to that
shown in Fig. 1.30 of Chapter 1. When the
bolts are free, remove them with their
washers.
42Lift the cylinder head from the block. If it is
stuck tight, insert pieces of wood into the
exhaust or inlet ports and use them as levers
to “rock” the head off the block. On no
account drive levers into the gasket joint orattempt to tap the head sideways as it is
located on positioning dowels.
43Remove and discard the cylinder head
gasket and both manifold gaskets.
44The cylinder head can be dismantled after
removing the camshaft and cam followers as
described in the preceding sub-Section.
45Further dismantling and decarbonising are
described in Chapter 1, Section 39. Note that
single valve springs are used.
46If the valves have been ground in, the
valve clearances will require adjusting, as
described previously. This should be done
before the cylinder head is refitted to the
engine.
47Before refitting the assembled cylinder
head, make sure that the head and block
mating surfaces are perfectly clean, and that
the block bolt holes have been cleared of any
oil.
48The camshaft sprocket timing mark must
be aligned with the one on the cylinder head.
49The new gasket should not be removed
from its nylon cover until required for use. Fit
the gasket dry to perfectly clean surfaces.
50Place the gasket on the cylinder block so
that the word ALTO can be read from above
(photos).
51Lower the cylinder head onto the block so
that it locates on the positioning dowels
(photo).
52The cylinder head bolts must have clean
threads, dipped in engine oil and allowed to
drain for thirty minutes. Screw the bolts infinger-tight and then tighten them in the
sequence shown in Fig. 1.30 of Chapter 1,
and in the stages specified (see Specification)
(photos).
53Refit the inlet manifold and carburettor
using a new gasket.
54Reconnect the exhaust manifold using a
new gasket. Tighten all nuts to the specified
torque. Reconnect the exhaust downpipe
bracket.
55Reconnect the timing belt and tension it
as described earlier.
56Refit the timing belt cover and the
distributor cap and camshaft cover.
57Reconnect all hoses, electrical leads and
controls.
58Fit the air cleaner.
59Fill and bleed the cooling system.
Supplement: Revisions and information on later models 13•23
5B.50A Cylinder head gasket5B.34 Inlet manifold coolant hose (A) and
brake servo vacuum hose (B)5B.32 Disconnecting the throttle cable
5B.52B Typical disc for angular tightening
of cylinder head bolts
5B.50B Cylinder head gasket top surface
marking
5B.52A Inserting a cylinder head bolt5B.51 Fitting the cylinder head
13

99Tighten the big-end bolts to the specified
torque (photo). The correct torque is
important as the bolts have no locking
arrangement. After tightening each big-end,
check that the crankshaft rotates smoothly.
100Repeat the operations on the remaining
piston/rod assemblies.
101Refit the oil pump pick-up assembly
using a new sealing ring.
102Refit the sump pan and the cylinder head
as described in earlier sub-Sections.
103Fill the engine with oil and coolant.
Pistons/connecting rods -
separation and piston
ring renewal
ª
104If the piston/connecting rods have been
removed in order to renew the piston rings,
refer to Chapter 1, Section 18, but note thatthe piston rings should be fitted so that the
word TOP is uppermost.
105If new pistons are to be fitted, it is
recommended that the gudgeon pins are
removed and refitted by a FIAT dealer as the
connecting rods must be carefully heated in
order to be able to push the gudgeon pin out
of the rod small-end, change the piston and
push the pin back into position. Locating the
gudgeon pin will require a special tool. The
gudgeon pin is a sliding fit in the piston but an
interference fit in the connecting rod.
106Refer to Fig. 13.6 for the correct
assembly of the piston and connecting rod.
Engine/transmission mountings
- renewal
107Refer to Chapter 1, Section 33. Three
mountings are used (photos).
PART C: ENGINE REMOVAL
AND DISMANTLING
Method of removal - general
1The engine, complete with transmission,
should be removed upwards out of the engine
compartment.
Engine/transmission -
removal and separation #
Warning: Refer to the beginning
of Section 9 before starting any
work.
2Mark the position of the hinges on the
underside of the bonnet and then, with the
help of an assistant, unscrew the hinge bolts
and lift the bonnet to a safe storage area.
3Drain the coolant; a cylinder block drain
plug is not fitted.
4Drain the engine and transmission oils.
5Disconnect the battery, negative lead first.
6Remove the air filter.
7Disconnect the radiator hoses from the
engine (photos).
13•26 Supplement: Revisions and information on later models
5C.7B Radiator hose at thermostat
housing5C.7A Radiator hose connection to coolant
distribution tube5B.107C Right-hand engine mounting
5B.107B Left-hand rear
engine/transmission mounting5B.107A Left-hand front
engine/transmission mounting
Fig. 13.6 Piston/connecting rod correctly
assembled - 999 and 1108 cc engine
(Sec 5B)
1 Piston grade (A) and directional arrow on
piston crown (towards timing belt)
2 Rod/cap matching numbers
3 Gudgeon pin offset in piston (0.9 to 1.1 mm)
Arrow indicates crankshaft rotation direction
Fig. 13.5 Piston ring arrangement on the
999 cc engine (Sec 5B)5B.99 Tightening a big-end cap bolt

can be lowered to rest on the exhaust and
bodymember.
34Continue to raise the engine and the
transmission until it can be removed from the
engine compartment and placed on the work
surface (photo).
35Clean the exterior of the engine and
transmission by steam cleaning or using a
water soluble solvent.
36Unbolt and remove the starter motor.
37Unscrew the flywheel housing-to-engine
flange bolts. Note the location of the engine
lifting lug.
38Unbolt and remove the lower cover plate
from the flywheel housing.
39Pull the transmission from the engine. It is
located by two hollow dowels and one stud
(photo).
Dismantling - general
40Refer to Chapter 1, Section 14.
Complete dismantling#
Warning: Refer to the beginning
of Section 9 before starting any
work.
41Unbolt and remove the camshaft cover.
42Unbolt and remove the timing belt cover.
43Remove the distributor (Section 10).
44Remove the hot air collector and the
exhaust manifold.
45Release, disconnect and remove the
coolant distribution pipe from the rear of the
coolant pump.46Unscrew and discard the oil filter
cartridge.
47Unbolt the thermostat housing, discard
the joint gasket.
48Remove the fuel pump, together with its
insulator block and actuating pushrod, if
applicable.
49Remove the carburettor, or throttle body,
as appropriate.
50Remove the inlet manifold and discard the
joint gasket.
51Remove the alternator and its drivebelt
and withdraw the engine oil dipstick.
52Unbolt and remove the crankshaft pulley.
53Unbolt and remove the timing belt
tensioner.
54Remove the timing belt.
55Unbolt and remove the coolant pump.
56Remove the cylinder head.
57Remove and discard the cylinder head
gasket.
58Remove the clutch.
59Lock the flywheel starter ring gear teeth
and remove the crankshaft sprocket bolt and
sprocket.
60Unbolt and remove the sump pan,
then the exhaust pipe support bracket
(photos).
61Prevent rotation of the crankshaft by
locking the starter ring gear teeth and then
unbolt and remove the flywheel. The flywheel
can only be fitted in one position as it is
located on a dowel.
62Remove the engine rear plate. Note thesmall socket-headed screw which holds the
timing index plate (photo).
63Unbolt and remove the oil pump pick-up
assembly, followed by the oil pump itself.
64Turn the engine on its side and remove
the piston/connecting rod assemblies.
65Stand the engine on its cylinder block
machined face, and then unbolt and remove
the crankshaft rear oil seal retainer. Discard
the gasket.
66Note the markings on the main bearing
caps. One line on the cap nearest the timing
belt, then two, C for centre cap, then three
and four (photo).
67The caps will only fit one way round.
68Unbolt the main bearing caps, removing
them with the shell bearings.
69Lift the crankshaft from the crankcase and
remove the bearing half shells from the
Supplement: Revisions and information on later models 13•29
5C.39 Separating the engine and
transmission5C.34 Lifting out the engine and
transmission5C.32 Right-hand engine mounting
brackets on body and engine
5C.66 Main bearing cap markings
5C.60A Removing the sump pan
5C.62 Unscrewing socket-head screw
from timing index plate5C.60B Exhaust pipe support bracket
attached to crankcase
13

tighten the sprocket bolt to the specified
torque (photos).
17Refit the clutch to the flywheel asdescribed in Chapter 5. Make sure that the
driven plate is centralised.
18Fit the cylinder head.
19Refit the coolant pump. A conventional
gasket is not used at the joint face, but apply
a continuous bead of RTV silicone instant
gasket 3.0 mm in diameter to the pump
mating surface. Allow at least one hour for
curing before permitting coolant to contact it.
20Fit the timing belt rear cover, then the
timing belt tensioner and lock in its retracted
position (photo).
21Fit and tension the timing belt as
described in sub-Section B.
22Bolt on the crankshaft pulley (photo).
23Refit the alternator and drivebelt (photo).
24Refit the engine oil dipstick.
25Using a new gasket, bolt on the inletmanifold, tightening the nuts to the specified
torque (photos).
26Refit the carburettor, or throttle body, as
appropriate.
27Fit the fuel pump, insulator block and
actuating rod, if applicable. Make sure that a
new gasket is placed on each side of the
pump insulator block.
28Using a new gasket, bolt on the
thermostat housing.
29Oil the sealing ring of a new oil filter
cartridge and screw it into position using hand
pressure only (photo).
30Refit the coolant distribution pipe to the
rear of the coolant pump. Use a new seal
(photo).
31Using a new gasket, bolt on the exhaust
manifold (photo).
13•32 Supplement: Revisions and information on later models
5D.31 Exhaust manifold5D.30 Coolant distribution pipe5D.29 Oil filter cartridge and mounting
base
5D.25B Fitting the inlet manifold5D.25A Inlet manifold gasket5D.23 Alternator and drivebelt
5D.22 Crankshaft pulley installation
5D.20 Fitting the timing belt rear cover5D.16B Tightening the crankshaft sprocket
bolt5D.16A Crankshaft sprocket showing
integral key

32Fit the hot air collector plate for the air
cleaner (photo).
33Refer to Section 10 and fit the distributor.
34Bolt on the timing belt cover.
35Fit the camshaft cover, using a new
gasket unless the original one is in perfect
condition.
Engine/transmission -
reconnection and refitting#
36Locate the engine in an upright position
on wooden blocks to allow for the greater
depth of the transmission flywheel housing
when it is joined to the engine.
37Make sure that the clutch driven plate has
been centralised, offer the transmission to the
engine and locate the flywheel housing on the
single stud and dowels.
38Tighten the connecting bolts to specifiedtorque, having located the lifting eye (photo).
39Bolt on the starter motor.
40Refit the cover plate to the flywheel
housing, but do not insert the lower bolts at
this stage as they retain the support bracket
for the gearchange rod.
41The engine and transmission are now
ready for refitting. The operations are a direct
reversal of the operations described earlier,
but observe the following points.
42Have the engine/transmission perfectly
horizontal and suspended on the hoist.
43Lower it into position very slowly until it is
possible to engage the driveshaft inboard
joints with the transmission.
44Continue lowering until the driveshafts
can be fully engaged and the mountings
reconnected. Remove the hoist.
45Tighten all nuts and bolts to the specifiedtorque. Note the method shown for
connecting the gearchange rod ball socket
using pliers (photo).
46Refill the engine with oil and coolant and
replenish the transmission oil.
Initial start-up after major
overhaul
47Refer to Chapter 1, Section 45.
6 Engine-
1301 cc Turbo ie
PART A: GENERAL
Description
1This engine is similar in design to the
1301 cc engine described in Chapter 1, but
the fuel and ignition systems are different, and
a turbocharger, oil cooler and intercooler are
fitted.
2Many dimensions and tolerances have
been altered for this engine, and reference
should be made to the Specifications at the
beginning of this Supplement.
3Operations which differ from those
described in Chapter 1 are given in the
following sub-Sections.
Lubrication system - description
4The lubrication system differs from the
non-Turbo 1301 cc engine in the following
respects.
5An oil cooler is fitted, which comprises a
matrix with inlet and outlet hoses connected
to the oil filter cartridge mounting base.
6A thermostatic control switch is fitted,
which diverts the oil flow through the matrix
only at oil temperatures above 84ºC (183ºF).
Note that a faulty switch will require renewal
of the complete oil filter mounting base.
7Special oil spray nozzles are located in the
crankcase main bearing webs, to cool the
underside of the pistons.
8The ball-type valves in the nozzles open
when the engine oil pressure reaches 1.2 bars
(17.4 lbf/in
2).
9An oil pressure sender unit is screwed into
Supplement: Revisions and information on later models 13•33
5D.45 Connecting ball socket type
gearchange rod5D.38 Lifting eye on flywheel housing
flange5D.32 Air cleaner hot air collector plate
Fig. 13.10 Cutaway view of the 1301 cc Turbo ie engine (Sec 6A)
13

Engine oil cooler -
removal and refittingÁ
23The oil cooler is mounted behind the front
bumper/spoiler (photo).
24Disconnect the oil flow and return hoses,
either from the cooler or the oil filter cartridge
mounting base. Be prepared for some
leakage of oil (photos).
25Unscrew the mounting bolts and remove
the oil cooler heat exchanger (photo).
26When refitting, make sure that the banjo
union sealing washers are in good condition.
PART C: ENGINE REMOVAL,
DISMANTLING, REASSEMBLY
AND REFITTING
Engine/transmission -
removal and separation
#
Warning: Refer to the beginning
of Section 9 before starting any
work.
1Refer to Chapter 1, Section 35, and carry
out the operations described in paragraphs 1
to 11.
2Disconnect the excessive air pressure
switch from the inlet manifold.
3Disconnect the ducts and remove the
airflow meter.
4Disconnect the leads from the spark plugs
and the distributor LT connector, and unbolt
and remove the distributor from the rear end
of the camshaft carrier.
5Disconnect the fuel return hose from the
pressure regulator. 6Disconnect the fuel inlet hose from the
injector rail.
7Disconnect the wiring plugs from the fuel
injectors.
8Disconnect the leads from the oil pressure
sender unit, the low oil pressure switch and
the coolant temperature switch.
9Remove the hose/pipe assemblies from the
intercooler.
10Disconnect the throttle control rod at the
balljoint.
11Disconnect the hoses and ducts from the
turbocharger and the mechanical bypass
valve.
12Disconnect the leads from the engine
speed and anti-knock sensors.
13Raise the front of the car and support it
securely. As the engine/transmission will
eventually be lowered to the floor, make sure
that there is sufficient clearance under the
front end for the assembly to be withdrawn. If
the car is over an inspection pit, then the car
need only be raised enough to lift the
roadwheels from the floor.
14Remove the front roadwheels.
15Disconnect the transmission earth cable.
16Working under the car, remove the engine
shields from under the wheel arches.
17Remove the engine oil cooler, and the
intercooler.
18Unscrew the fixing screws and disconnect
the driveshafts from the flanges at the
transmission final drive. The right-hand
driveshaft will not release until the upper bolt
on the suspension strut-to-hub carrier clamphas been removed, and the hub assembly
tilted downwards.
19Disconnect the exhaust downpipe from
the manifold, and then remove the front
section of the exhaust system.
20Disconnect the coolant return pipe from
the turbocharger.
21Disconnect the gearchange control rods
from the transmission selector rod. Do this by
unscrewing the self-locking nut from the bolt
which connects the clevis fork.
22Attach suitable lifting gear to the engine
lifting eyes, and take the weight of the
engine/transmission.
23Disconnect the left-front, centre-rear and
the right-hand engine/transmission mountings.
Do this by removing the bolts from the
diamond-shaped mounting plates there is no
need to disturb the flexible mounting centre
bolts.
24Lower the engine/transmission to the floor
and withdraw it from under the car.
25Carry out the operations described in
Chapter 1, Section 35, paragraphs 27 to 31.
Engine dismantling and
reassembly
26The operations are essentially as
described for the 1301 cc engine in Chapter 1,
but reference must be made to Sections 9
and 10 of this Chapter for the procedures for
removing and refitting the components of the
fuel injection, turbocharger and ignition
systems.
Engine/transmission -
reconnection and refitting
27The operations are a reversal of those
described in paragraphs 1 to 25, but
otherwise the following (photo).
a) Tighten all nuts and bolts to the specified
torque.
b) Use a new gasket at the exhaust
downpipe-to-manifold flange.
c) Check and adjust the clutch pedal travel.
d) Refill the cooling system.
e) Refill the engine and transmission with oil.
f) Reconnect the battery, negative lead
last.
13•36 Supplement: Revisions and information on later models
6C.27 Filling the engine with oil6B.25 Oil cooler mounting bolts (arrowed)
6B.24B Connections at oil filter cartridge
mounting base6B.24A Oil cooler pipe connection
(arrowed)6B.23 Oil cooler